package tracing;
public class Main
{
	public static void main(String[] args)
	{
		X x = new X();
		Y y = new Y();
		X x2 = new X(3);
		Y y2 = new Y('a', "Alex");
		x.foo();
		x.bar(y2);
		y.uno();
		y.dos();
		
		try
		{
			y.tres();
		}
		catch (NullPointerException e)
		{
		}
	}
}
